Stepped (4)
'stepped' is the definition.
('tread' can be a synonym of 'step')
This is all the clue.
(Other definitions for trod that I've seen before include "Walked heavily, put foot down" , "Took steps" , "start making wine" , "Stepped heavily" , "Trampled" .)
'stepped' is the definition.
(to pace is to take a step)
This is the entire clue.
(Other definitions for paced that I've seen before include "Took steps" , "Made anxious moves" , "set the tempo" , "assist an athlete" , "Walked at a steady speed" .)